Gas assist molding is a low-pressure plastic injection molding process where pressurized nitrogen gas is injected into the mold, pushing the plastic into the mold extremities, while hollowing out thicker sections in the part.
In the gas assist molding process, the plastic material is melted and injected into the mold cavities via the conventional plastic injection molding process. Plastic material in contact with the mold walls begins to solidify first. As this happens, nitrogen gas is injected into the mold through strategically designed and placed gas channels, providing pressure that pushes the plastic material into the mold extremities. Once the plastic cures, the nitrogen is vented and the gas assist injection molded plastic parts are removed from the mold. Gas assist injection molding process animation.